Fire extinguisher



Feb. 4, 1958 J. w. HOWARD l v2,822,054

FIRE EXTINGUISHER Filed May 9, 1955 t INVENTOR. JOHN w. HOWARD United States Patent O FIRE EXTINGUISHER John W. Howard, Los Angeles, Calif., assignor to The General Pacific Corporation, Los Angeles, Calif., a corporation of California Application May 9, 1955, Serial No. 506,960

1 Claim. (Cl. 169-31) This invention relates generally to tire extinguishers and more particularly to a portable, stored pressure type of tank extinguisher. Although the invention will be described with reference to pressurized extinguishers, it will be apparent that the features disclosed are also applicable to other types of extinguishers.

Conventional pressurized extinguishers include a tank lled with uid to a given level. The remainder of the tank volume is then charged with compressed air. The level of the fluid within the tank will, thus, determine the volume occupied by the compressed air charge. From both the standpoint of proper engineering design and effective operation of the tire extinguisher, it is important that the air space be of a given volume according to the capacity and characteristics of the particular extinguisher. The necessity for accurate measurement oftentimes presents problems to the user who may be frequently refilling and recharging an extinguisher, or who may have to relll the extinguisher under emergency conditions. ln addition, it is apparent that an error will result in an incorrect air space volume, thereby affecting the satisfactory operation of the extinguisher.

One object of the present invention accordingly is to provide an improved lire extinguisher, which may be filled with fluid to a given level without the necessity of measuring the iluid poured into the extinguisher.

Another troublesome difficulty with present day extinguishers is the requirement of removing the head assembly in order to expose the opening in the tank through which the lluid is received.

It is therefore another object of the present invention to provide a head assembly of such a construction that it need not be removed during refilling and recharging of the extinguisher.

Another object is to provide an extinguisher embodying the previous objects, which may be competitively and economically manufactured.

A still further object is to provide an improved extinguisher embodying the above objects which is rugged and safe in its construction and yet which may be simply operated and easily maintained.

These and other objects and advantages of the present invention are attained by providing a member extending downwardly from the standard tank opening, to a given level within the tank. The member is provided with an internal passage throughout its length which communicates in sealed relationship with the opening in the tank.

In a preferred embodiment, there is additionally provided a head assembly for connection to the tank. The head assembly includes an associated valve body having a fluid passage extending through it. The fluid passage in the valve body is also adapted -to communicate with the tank opening when the head assembly is secured to the tank.

As a result, fluid may be poured directly into the uid passage and will thereafter flow down through the tank opening, eliminating the necessity of removing the head 2,822,054 Patented Feb. 4, 1958 ice assembly during the filling operation. When the fluid reaches substantially the given level, it will rise only in the passage within the downwardly extending member until overflow occurs. Any tendency for the fluid to rise within the now closed air chamber, defined between the outer periphery of the member and the tank walls, is prevented because of an increased air pressure in the chamber which equalizes to the sum of the Huid head within the member and the atmospheric pressure to which the uid head is exposed.

A better understanding of the present invention will be had by reference to the drawings, in which:

Fig. 1 is a vertical broken away sectional view of a preferred embodiment of the improved re extinguisher; and

Fig. 2 is a view taken in the direction of the arrows 2-2 of Fig. 1.

There is shown in Fig. 1 an improved fire extinguisher according to the present invention comprising a tank 10 and an associated head assembly, generally designated by the numeral 11. The head assembly 11 includes a valve body l2 having a lower threaded portion 13 screwed into an internally threaded boss 14 provided at the top of the tank 10.

A handle 15 is secured to the valve body 12 by a rivet 16. The handle 15 is concave in cross-section and has partially disposed within it an uplock 17, which is shown attached to the handle by a rivet 18. The uplock 17 is provided to lock the handle 15 to the valve body 12 when the handle 15 is disposed in a horizontal or operating position. For this purpose the uplock is provided with a hooked end 19 adapted to be received in a recess 20 in the valve body 12. The end 19 is biased into position in the recess 20 by a spring 21 secured to the rivet 18' about which the uplock 17 may pivot. In the view of Fig. l, the handle 15 is shown in its vertical position enabling more convenient storage and shipping. When the extinguisher is to be operated, the handle 15 is raised to a horizontal position, whereby the end 19 will snap into the recess 20, thereby locking the handle against downward movement. To lower the handle, the uplock 17 may be pivoted by linger pressure into the position in Fig. l so that the end 19 clears the recess 20.

The head assembly 11 further includes a lever 22 secured to the valve body 12, as by a rivet 23. The lever 22 is also concave in cross-section so that its sides may be disposed over the valve body. The lever 22 may be locked in the non-operating position of Fig. l by inserting a pin through the bore 24 in the valve body 12. Registering apertures may be provided in the sidewalls of the lever 22 for this purpose.

Disposed within the tank l0 is a syphon assembly, generally designated by the numeral 25, including a flexible tubing 26 having fastened to its bottom end a weight member 27. The weight 27 serves to move the tubing 26 in a direction corresponding to any particular inclined position of the tank 10, thereby insuring that the bottom of the tubing will always be disposed under the iluid level. The flexible tubing 26 terminates at its upper end in an annular nut 28, provided with external threading for securing within an internally threaded portion of the valve body 12. The nut 28 presses against an annular seal 29 disposed'within the valve body.

Positioned concentrically within the nut 28 is a helical spring 30, which biases a plunger 31 upwardly. The plunger 31, extends up through the valve body 12 a given distance so that its upper end is positioned under the lever 22. An O-ring 32 may be disposed about the plunger 31 for sealing purposes. Thus, upon depression of the lever 22, the plunger 31 will be urged downwardly to overcome the force of the spring 30 and thereby 3 unseat the plunger from the seal 29. With the plunger so depressed, an air passage 33 will communicate from a nozzle 34 on the valve body 12 clown through the tubing 26.

Within the tank 10, there is shown coaxially disposed around the tubing 26, a tube member 35 having a flared upper end 36 confined between the threaded portion 13 and an annular gasket 37 positioned on a bevelled inner edge surface of the threaded portion.

An important feature of the present invention resides in the provision of the member 35. The member 35 is accurately cut to a given length so that it will extend down into the tank to a predetermined level L. Although the member 35 has been shown with a circular crosssection is the preferred embodiment chosen for illustrative purposes, members with non-circular cross-sections are feasible.

In the view of Fig. 1, the tank is shown filled with fluid 38 to a height exterior of the member 35, slightly above the level L. The liuid 38 will also occupy the entire inner passage within the member 35 if the extinguisher has been lled to the point of overow. These conditions will become clearer when the operational features of this improved extinguisher are described. The remaining upper portion of the tank forms with the member 35, an annular air chamber 39 occupied by a compressed air charge. The volume of this compressed air chamber 39 will be established, assuming a given inner cross-sectional area for the member 35, according to the level L to which the member 35 extends down into the tank 10.

As may be seen from the view of Fig. 2, the valve body 12 has extending through it a tiuid passage 40 communicating with the inner portion of the tubular member 35. When the extinguisher is not being filled, this uid passage 40 may be closed oif by a fill cap 41. It will thus be apparent that there is no need to remove the head assembly 11 during the filling operation. The cap 41 need only be removed and uid will flow down through the passage 40 into the tube member 35 and thereafter into the tank 10.

If desirable, a pressure gage 42 may also be connected to the valve body 12, as by a threaded extension 43, which has passing through it a passage 44 operably connecting the gage to the fluid passage 40.

In operation, the cap 41 is removed and extinguisher uid is poured into the passage 40. The fluid 38 will rise in the tank 10 to a height, as previously described, slightly above the level L to which the bottom of the member 35 extends. The height to which the fluid rises exterior of the member 35 is limited since once the uid 38 closes olf the bottom of the member 35, the annular air chamber 39 will also be closed off to free flow of air. Consequently, as the tluid rises further on the exterior of the member 35, there will necessarily be a decrease in volume of the air chamber 39 with a proportional inf crease in pressure. This resultant increase in pressure will prevent further fluid from filling the air chamber 39 whereby fluid poured into passage 40 will pass up through the tube member 35 until it overllows. The fluid will necessarily rise a slight distance above the level L until the resulting higher pressure in the chamber 39 balances the uid head within the member 35 together with the atmospheric pressure exerted on this fluid head, whereby a state of equilibrium is reached.

Once the uid 38 has been received into the tank, ex-

tinguisher may be charged with compressed air. This may be simply done by connecting a conventional tire chuck or the like to the nozzle 34. The plunger 31 will be pressed downward as a result of the air pressure overcoming the spring force. The air will then ow through the passage 33, down through the tubing 26, and out the bottom opening of the tube to pass up into the closed annular air chamber 39. After the desired pressure has been reached, as determined by the gage 42, the chuck is removed. The plunger 31 will then be biased back against the seal 29 to close off the passage 34.

The discharge of the extinguisher is readily accomplished in a conventional manner by first raising the handle 15 to a horizontal, gripping position and then pressing down on the lever 22. The plunger 31 will be correspondingly depressed, and the compressed air charge in the chamber 39 will force the tluid 38 up through the flexible tubing 26 and thereafter through the passage 33 and out the nozzle 34.

From the foregoing description, it will be appreciated that the improved lire extinguisher of the present invention allows expeditious filling of the extinguisher without the necessity of disassembling any of the major components of the extinguisher and without the need of measuring the fluid being poured into the extinguisher.

The invention is not to be thought of as limited to the particular embodiment shown, but rather to encompass changes and modifications, as covered within the spirit and scope of the following claim.

What is claimed is:

In a re extinguisher including a tank with a tank opening through which uid may be received: a head assembly coupled to said tank; a valve body incorporated in said head assembly, said valve body including a nozzle opening and a till opening on the surface thereof; a member supported from said tank and extending downwardly from said tank opening to a given level within said tank, said member having an internal passage throughout its length communicating in sealed relationship with said tank opening; a siphon tube extending axially through said internal passage of said member, said siphon tube having one end connected to said valve body and its other end extending down into a bottom portion of said tank; a first passage extending through said valve body and communicating between said one end of said siphon tube and said nozzle opening; a valve member positioned in said rst passage; and, a second passage extending through said valve body and communicating between said fill opening and said internal passage of said member, whereby fluid may be poured into said fill opening to pass down into said tank opening through said second fluid passage without removal of said head assembly and whereby the uid received will first fill said tank to substantially said given level and thereafter iill only said internal passage of said member.

References Cited in the le of this patent UNITED STATES PATENTS 713,946 Brischar Nov. 18, 1902 1,776,807 Gosman Sept. 30, 1930 2,001,394 Norgren May 14, 1935 2,129,465 Dodelin Sept. 6, 1938 2,620,746 Beauregard Dec. 16, 1952 2,644,313 Griggs July 7, 1953 

